The present invention relates to a bending die for forming a bend in a tube, and in particular to a bending die with a release feature to facilitate removing the tube from the bending die after forming the bend.
Bending dies are commonly used to form bends in tubes so that the tubes do not collapse when forming the bends, but rather take on the particular shape desired. Typically, the bending dies have a groove formed in one or more sides of the bending die to hold the tube while the bend is being formed, the groove having a semicircular shape that supports the cross-sectional shape of the tube around the inside of the bend to prevent the tube from collapsing.
However, tubes requiring one or more 180.degree. bends present special problems. For example, since the groove extends onto opposing sides of the bending die in order to form the 180.degree. bend, the tube becomes deadlocked in the groove once the 180.degree. bend is formed. Thus, the tube can only be removed from the bending die by sliding the bent tube linearly off an end of the bending die. However, sliding the bent tube linearly off an end of the bending die is time consuming and slows production, and further creates a cumbersome and inefficient unloading process. Still further, as additional 180.degree. bends are formed, the portion of the tube already formed may interfering strike the backside of the bending die or the bending press as the bent tube is being linearly removed, thus preventing the machine from making a finished part in a single continuous process.
One known bending die for making a bend in a tube has an upper die half and a lower die half adapted to be manually disassembled and split apart after forming the bend so that the bent tube can be removed. This known bending die is disclosed in the Information Disclosure Statement submitted herewith. However, the manual assembly/disassembly of the die halves for each bend is labor intensive and time consuming. Despite this, the manual operation continues to be used since automating the split die arrangement has not been considered practical. For example, automation takes up space around the bending dies and creates zones of interference that are difficult or impossible to work around where the tube is manipulated back and forth to form multiple bends. Further, automating the split die arrangement has been considered economically prohibitive since automation is expensive to purchase and maintain, and further often requires complex and expensive controls, which automation and controls are generally not useable on other jobs.
Thus, an improved bending die is desired for solving the aforementioned problems.